The present application relates to bonded channels for increasing wireless transmission bandwidth.
The impressive growth of cellular mobile telephony as well as the number of Internet users promises an exciting potential for cellular wireless data services. As demonstrated by the popularity of the Palm V wireless handheld computer, the demand for wireless data services, and particularly for high-performance wireless Internet access, is growing rapidly. However, the price/performance curve for existing cellular data services can still be enhanced. One reason for the current price/performance curve stems from the fact that current wireless data services are based on circuit switched radio transmission. At the air interface, a complete traffic channel is allocated for a single user for the entire call period, which can be inefficient for bursty traffic such as Internet traffic. For bursty Internet traffic, packet switched bearer services result in better utilization of the traffic channels because a channel will only be allocated when needed and will be released immediately after the transmission of the packets. With this principle, multiple users can share one physical channel (statistical multiplexing).
In order to address these inefficiencies, two cellular packet data technologies have been developed: cellular digital packet data (CDPD) (for AMPS, IS-95, and IS-136) and the General Packet Radio Service (GPRS). GPRS is a bearer service for GSM that improves and simplifies wireless access to packet data networks. GPRS applies a packet radio principle where packets can be directly routed from the GPRS mobile stations to packet switched networks. In a GSM/GPRS network, conventional circuit switched services (speech, data, and SMS) and GPRS services can be used in parallel: a class A mobile station supports simultaneous operation of GPRS and conventional GSM services; a class B mobile station is able to register with the network for both GPRS and conventional GSM services simultaneously, but can use only one service at a time; and a class C mobile station can attach for either GPRS or conventional GSM services, but cannot simultaneously register and use the services. GPRS improves the utilization of the radio resources, offers volume-based billing, higher transfer rates, shorter access times, and simplifies the access to packet data networks.
One evolution of GPRS is called EDGE (Enhanced Data for Global Evolution). EDGE uses 8 PSK modulation that automatically adapts to local radio conditions, offering the fastest transfer rates near to base stations in good conditions. It offers up to 48 kbps per channel, compared to 14 kbps per channel with GPRS and 9.6 kbps per channel for GSM. By allowing simultaneous use of multiple channels, EDGE allows rates of 384 kbps using all eight GSM channels. However, even the improved data transfer rate in GPRS is insufficient for certain applications, for example data visualization, real-time imaging, video on demand, video streaming, video conferencing, and other multimedia applications.